As you give extra time and attention to your older child who is experiencing some sleep regression, be careful to not create a new sleep crutch such as holding his hand till he goes to sleep, lying down with him each night, or letting him listen to an audiobook at bedtime till he goes to sleep. (blog.cloudb.com)
The older your baby is, the more resistance you are likely to be met with, as older babies have had longer to learn habits and often rely on sleep crutches to get them to sleep. (sleeptrainmybaby.com)
Indeed the bottle and pacifier are both sucking actions and can be sleep crutches so addressing one alone wont do the trick! (sleeplady.com)